arc feed adjustment q'

[glenthemann]

Hey, so I noticed this option and thought it was great in that i could set a minimum feed and it would calculate the arc feeds so that the cutting edge was moving at the feed I wanted..

Only, its making the feeds super small when I am machining curves from the outside.. that makes the cutting feed even SLOWER than what I want.

I understand that say, if I am milling a circle into a part, that the outside of the cutting edge will be moving at a feed a lot faster than the tool path, but if I am milling a circle into the outside, then the cutting edge is moving slower than the tool path itself..

Why does it make the arc super slow when it should infact be speeding it up?

I am working with mastercam mill 9.

[glenthemann]

no one?

[Delw]

Does it automatically change the feed in the program? ( ie can you see a different "F" number) if not then maybe you machine is adjusting for arc feed check to see if there is a parameter set up for this( I forget the proper term).


if mastercam is putting in a slower speed than you should be able to see it easy enough in the tool feeds and speeds menu.

Delw

[glenthemann]

I thought I had pretty much explained that I checked the option and it was adjusting the feeds for arcs in the opposite direction. I didnt even mention it running in the machine, but what you said sounds like it would be something good to check out.

The smaller the arc to be machined, the slower the feed, when in fact it should be the other way (this would be correct if I was milling a bore or some sort of pocket)

I know I must be missing something somewhere, Im just not sure what.

So to clarify, yes there are feed changes on any g2 command, and they are in the opposite direction than I intended them to be (smaller feeds instead of increased feeds)

[Ydna]

I always assumed it was a feature meant to be used specifically on internal pockets. Because it's there that a lack-of-feedrate-decrease might substantially change the workpiece. On the outside everything still ends up good, just some time wasted (and other stuff I suppose, depending how theoretical you want to get). So having said that I doubt there's a way to do what you're looking to do since it was probably not intended....but I'm not an expert so if someone else knows if it's possible I'd love to read it..

[Changedsoul]

Hello, I know this is a bit late in response, but hacked exactly what your looking to do into one of my posts. Im a Lathe guy and got sick of my turning tool flying through radii in corners, so I hacked a MISC Int in the post as a toggle. When set to one, it will speed feeds up on outside corners, and slow them down on inside corners to keep the tool moving at a constant feed along the surface of the part.

If your still interested, I can clean it up a bit and email it to you.